Recent advances in compression technology for digital music data have made it possible to compress digital music data to be downsized to, for example, about 1/10 of its original size while hardly impairing the sound quality of the original digital music data, and numbers of such compression techniques are proposed. For example, in the case of a tune of about five minutes long which has almost the same sound quality (data bit: 16 bit, sampling frequency: 44.1 kHz) as a CD (Compact Disk), the tune is converted to digital data of about 50 MB in a normal state. However, when adopting a sound compression technique as discussed to convert a data format of the data of the tune, the data can be compressed to the extent of about 5 MB. The data of about this size, for example, can be downloaded to a general home PC (Personal Computer) via the Internet without much difficulty.
However, there arises a problem such that some websites convert music data stored in a commercially available CD into compressed data by utilizing the compression technology as above so as to illegally distribute the compressed data via the WWW (World Wide Web) over the Internet without obtaining the copyright holder's permission to do so.
In other words, since digital data has a characteristic that a quality of data is not impaired after being repeatedly copied, once digital data subject to a copyright is converted to data in a state which can readily be dealt with in a device free from a copy protect facility and capable of making copies, such as a PC, it is then theoretically possible to infinitely and easily make duplicates of the data subject to the copyright. In that case, the right of a copyright holder cannot fully be protected.
Against this problem, there is proposed a data distribution system capable of protecting a copyright in the distribution of music utilizing the Internet. Here, an example of such data distribution system will be explained.
In this data distribution system, distribution-use music data can be downloaded, for example, to a PC, only by paying for that by some payment methods, such as the one utilizing settlement by credit card. This distribution-use music data is an encoded data, which can be reproduced only by using a specific application software program.
Further, the downloaded distribution-use music data is written into a hard disk inside the PC and stored there in such a format that contains information of storage conditions. Thereafter, when it is instructed to reproduce the distribution-use music data, the application software compares the information of storage conditions stored in the distribution-use music data with the actual storage conditions of the distribution-use music data, and the music data is reproduced only when the both conditions are identical. The application software thus functions so as to allow the downloaded distribution-use music data to be reproduced only by the PC to which the data was downloaded.
Furthermore, the distribution-use music data can be copied predetermined limited number of times with respect to a predetermined recording medium. More specifically, the distribution-use music data includes in advance the information of available copy count. For example, when the distribution-use music data is first downloaded, the available copy count is set at three. Further, as to a recording media, a recording medium including an ID (IDentification) authentication facility is used.
Further, when the distribution-use music data in the PC is copied to a recording medium, ID authentication is first performed by the application software within the PC with respect to the recording medium to which the distribution-use music data is to be copied. When the ID authentication is duly performed, the application software transfers data containing the information of the recording medium to the recording medium. In addition, when performing copying with respect to the recording medium, the application software performs a process to subtract one count from the information of the available copy count contained in the distribution-use music data in the PC. Namely, in the case where the available copy count of the downloaded distribution-use music data is three, the data can be copied only to three recording media, and it can no longer be copied to other recording media. Note that, the application software forbids copying data from a copy of the same data, which was previously made in a recording medium, with respect to another recording medium.
Further, the application software enables “recovery” of data by placing a copy of the distribution-use music data in the recording medium back onto the PC. More specifically, in the case where the recording medium storing a copy of the distribution-use music data no longer needs that distribution-use music data, the application software erases the unwanted distribution-use music data from the recording medium and performs a process to add one count to the information of the available copy count of the distribution-use music data within the PC. For example, in the case where three copies of the distribution-use music data are already made in three recording media, respectively, but a further copy of the distribution-use music data should be made in another recording medium, it is possible that a copy of the distribution-use music data in one of the recording media is erased, and one count is thereby added to the information of the available copy count of the distribution-use music data within the PC, thereafter making a copy of the distribution-use music data in the desired recording medium.
With the data distribution system and the application software thereof as discussed, since distribution-use data which is once downloaded into a PC contains the information of storage conditions and the information of available copy count, and the operation of reproducing and/or copying the data is available only when the information is valid, it is possible to solve to some extent the foregoing problem as to protection of a copyright in relation to digital data.
However, the foregoing data distribution system has a problem as shown below.
For example, in the case where one desires to use distribution-use music data, which was once downloaded by paying for that and stored in a PC, in a different PC, it is not possible by simply copying a file from one PC to the other that the information of storage conditions in the different PC to which the data is to be copied coincides with the information of storage conditions contained in the distribution-use music data. As a result, reproducing and/or copying the distribution-use music data cannot be performed by the foregoing data distribution system and the application software thereof.
Consequently, in the case where a user desires to use (reproduce/copy) distribution-use music data in a PC which is other than a PC which was already used in downloading, the user should pay again for downloading the same distribution-use music data to the other PC. Namely, the user should pay twice and spend twice the time for downloading the same distribution-use music data.
Further, a problem also arises when, for example, something causes breakage in a program data of the OS (Operating System) in the PC, to which distribution-use music data was downloaded, and the OS should be reinstalled so as to recover the program data. In that case, a difference occurs between information in a storage state which is recorded in the distribution-use music data and information in a storage state in a PC after reinstallation. As a result, the distribution-use music data becomes unable to operate reproduction and copying. More specifically, in the case where the OS is reinstalled in the PC, the user should pay again for downloading the same distribution-use music data.
Further, the following is likely to happen: a user makes duplicates of distribution-use music data which was downloaded to the PC in recording media, where the number of the recording media (three, for example) is the same as the available copy counts; thereafter, the user desires to make a new copy of the data in a recording medium without deleting the copied data stored in the foregoing recording media. In that case, the user should pay again for downloading the same distribution-use music data and make a duplicate of the newly downloaded distribution-use music data in the other recording medium. Namely, the user should pay twice and spend twice the time for downloading the same data. Moreover, two copies of the distribution-use music data of the identical content are recorded in the same hard disk of the PC after all. This is no more than the useless occupation of the capacity of the PC hard disk.
As discussed, the foregoing data distribution system has a problem in terms of the user's convenience, though it is achieving a quite good level of copyright protection. This problem obstructs the spread of the foregoing data distribution system.
The present invention is made in order to solve the foregoing problems, and an object of which is to provide an information distribution system capable of distributing, via a communications network, data for distribution which contains contents data provided from an information source provider and of reusing the data for distribution which was distributed once.